"This you may eat from everything that is in the water, everything that has fins and scales... those you may eat" (Leviticus 11:9).

The Talmud (Niddah 51b) says that a fish that has scales also has fins and there is no need to examine for them. However, there are fish that only have fins and they are unclean.

What is the lesson we can derive from the signs of the kosher and non-kosher fish?

Fish in their habitat — water — are analogous to scholars studying Torah. This is obvious from that which is related in Talmud in connection to the Roman government's decree against Torah study. When Pappas ben Yehudah saw Rabbi Akiva convening public assemblies to study Torah he asked him, "Akiva are you not afraid of the regime?" Rabbi Akiva replied with a parable: "Once a fox was walking alongside the river bank and saw fish gathering from place to place, as they were fleeing something. When the fox inquired, 'From what are you running away?' They told him, 'From the nets people set up to catch us.' The fox said to them, 'Come up to dry land and we will dwell together just as our ancestors dwelled together.' The fish responded, 'You are a fool, for if in our habitat where our life is sustained we are afraid, all the more so we should be afraid for our existence if we leave our habitat.' Likewise, Rabbi Akiva said, "If now when we study Torah which is our lifesaver, our existence is threatened, how much are we in danger if we would absent ourselves from Torah."1

Scales serve as a protective garment to the fish and through the fins it swims from place to place.2 When one studies Torah it is expected of him to create innovative thoughts and explanations. It is also imperative that one who studies Torah have fear of Heaven. The Talmud compares Torah study with fear of Heaven to wheat which is stored with a preservative consisting of earth with a high salt content. Just as the grain will spoil quickly without the preservative, likewise, one studying Torah without fear of G‑d, will easily forget, and his Torah study will be like a poisonous medicine for him.3

Thus, the fins represent the power to accomplish and reach new heights through innovative contributions to Torah, and the scales represent the essential ingredient of fear of Heaven, through which one's Torah study is preserved and becomes a source of "medicine that adds life."

Consequently, if one possesses the quality of "scales," he is on the right track with his Torah study and will eventually enhance himself and the Torah with his "fins"--innovative thoughts which will be compatible to Torah truth. Such an individual is considered pure and clean. But one who studies Torah and does not have "scales"--fear of Heaven—is unclean and unfit. His Torah study and fins —innovations—are contrary to G‑d's desire and it does not merit him the spiritual source of life which Torah gives to those who study it.